Genidens Castelnau, 1855

Marceniuk, Alexandre Pires, Oliveira, Claudio & Ferraris Jr, Carl J., 2024, A new classification of the family Ariidae (Osteichthyes: Ostariophysi: Siluriformes) based on combined analyses of morphological and molecular data, Zoological Journal of the Linnean Society 200 (2), pp. 426-476 : 442

Genidens Castelnau, 1855

MP 100, BI 1, ML 100

( Figs 1–3 , 12B , 14 )

Type species: Bagrus genidens Valenciennes, 1840 .

Diagnosis

Temporal fossa very reduced (39, 1> 0); dentary teeth restricted to mesial two-thirds (116, 1> 0); posterolateral processes of urohyal short (160, 1> 0); posterolateral processes of urohyal two-thirds as long as distal portion of bone (162, 1> 2); posterior portion of second basibranchial short and wide (167, 2> 3).

Ambiguousoptimization: Mesialborderwithparieto-supraoccipital as long as distal portion of bone (36, 1> 0); tooth plates attached to vomer by ligaments (57, 0> 1); otolith posterior margin rounded (74, 1> 0); posterolateral processes of urohyal as long as or longer than distal portion of bone (162, 0> 1).

Included species

Genidens barbus (Lacepède, 1803)

Genidens genidens (Cuvier, 1829)

Genidens machadoi (Miranda Ribeiro, 1918)

Genidens planifrons (Higuchi, Reis & Araújo, 1982) .

Habitat and distribution: Brackish and marine waters, east and southern South America ( Fig. 12 ).

Remarks

Total-evidence analysis supports the monophyly of Genidens , as reported in previous phylogenetic studies (Betancur-R. 2009, Marceniuk et al. 2012), with a new hypothesis of relationships. The species of Genidens form a species flock, as evidenced by their shallow genetic divergences (Cerqueira et al, unpublished work).

Figures

Figure 1. MP analysis.Subfamilies (SF) Galeichthyinae (pink), Bagreinae (bright blue), and Ariinae (dark blue). Tribe (T) Ariini (blue), Cathopsini (orange), Genidentini tribe nov. (brown), and Sciadeini tribe nov. (light green).Subtribe (ST) Ariina (light blue) and Doiichthyina (green). Incertae sedis taxa (IS) (red). Numbers over branches correspond to the bootstrap support.

Figure 2. ML analysis. Subfamilies (SF) Galeichthyinae (pink), Bagreinae (bright blue), and Ariinae (dark blue). Tribe (T) Ariini (blue), Cathopsini (orange), Genidentini tribe nov. (brown), and Sciadeini tribe nov. (light green). Subtribe (ST) Ariina (light blue) and Doiichthyina (green). Incertae sedis taxa (IS) (red). Numbers over branches correspond to the bootstrap support.

Figure 3. BI analysis.Subfamilies (SF) Galeichthyinae (pink), Bagreinae (bright blue), and Ariinae (dark blue). Tribe (T) Ariini (blue), Cathopsini (orange), Genidentini tribe nov. (brown), and Sciadeini tribe nov. (light green).Subtribe (ST) Ariina (light blue) and Doiichthyina (green). Incertae sedis taxa (IS) (red). Numbers over branches correspond to the bootstrap support.

Figure 12. Representative skulls, in dorsal view, and distribution of Genidentini tribe nov. A, Chinchaysuyoa ortegai, MPEG 35976. B, Genidens genidens, MZUSP 51694. C, Paragenidens grandoculis, CIUFES 3763.* marine, ** brackish waters, *** freshwater.

Figure 14. Genidens genidens, western South Atlantic, photograph by Alexandre P. Marceniuk, type species of the genus.